( 196 ) 
ESSAY 
ON THE 
GEOGRAPHICAL HISTRIBUTIOH 
OP 
OPHIDIANS. 
In proposing to give, in the following pages, a sketch of 
the distribution of Serpents on the surface of the globe, I 
consider it necessary to enter into numerous details, with 
which I might have dispensed, if this part of the science 
had been previously cultivated, or if any one had al- 
ready laid the foundations. I have occupied myself with 
considerable zeal in this study, which merits an espe- 
cial attention — not merely because it regards the animals 
of which I treat in my work, but because it ought to 
lead, in my opinion, to results much more satisfactory than 
the study of the geographical distribution of the animals 
in the other classes of the Animal Kingdom, or even of 
Vegetables. The reasons in favour of this proposition 
are obvious. A thousand different agents contribute to 
disperse different species of plants over the surface of the 
globe ; the seeds of plants are carried by the winds and 
the waves ; man perpetually transplants a great number 
